I have never had or built a glider before. So this will be new for me. Any and all comments and pointers are not only welcome, but encouraged! I’ve also sent a message to Don Stackhouse who’s the designer of the Chrysalis and part owner of DJAerotech to see if he can follow along and give me some tips. He’s active over on RCGroups, hopefully he can come to WattFlyer as well.

The Chrysalis was originally designed for a Speed 600 and NiCad batteries. I’m planning to go brushless and use some of my LiPos I already have. So here is my current plan… If anyone else has some good ideas, please chime in!

My Goal is to have a lightweight plane that can accept many different batteries to adjust the final weight. That way I can go very light for when there is almost no wind, but heavier for windier days. I also do not have a lot of storage room, so I’m thinking of the three piece wing option. It would be great to end up with the plane weighing about 30 ozs without the battery.

I’m thinking of using a lightweight brushless motor in the 250 Watt range. This is about where the 480 sized motors are and you can find both 35-xx and 28-xx sized motors in this power range. The included firewall is made for a square 25 mm bolt pattern and a rear mount motor. So far I am thinking that the HeadsUpRc Firepower 480 would be a good fit.http://www.headsuprc.com/servlet/the...h-11%29/Detail
It’s a 260 Watt, 35-30 motor with a 25mm x 19mm bolt pattern. It should fit the included firewall with just creating two new holes. Since this motor weighs only 2.6 oz, I’m planning to stretch the nose by 1.5 to 1.75 inches as well. I have read about others doing that with good success. If I can keep the plane balancing neutral with the motor, then the batteries can still sit under the wing like in the original design.

The plane can optionally use either a conventional or V-tail setup. I’ve read that the V-tail is slightly lighter, so I’m planning on going that way. I also like the looks of a V-Tail better, so it’s a easy decision.

The amount of power you need depends on what you're planning to do with the plane. For basic sport flying, 180 watts is plenty, the plane will go nearly vertical on that. 250 watts could be good for some types of competition. Since you're planning to extend the nose, you don't need a lot of motor weight up front.

The plane was originally designed for a Speed 600, and an MP Jet 28/20-7 (5.7 ounces, outstanding motor, but unfortunately no longer available) weighs about the same. If you go with a lighter motor and the stock nose, you will end up having to add more weight further aft than what you save with the motor, just to get the correct C/G. However, the extended nose fixes that problem.

We are planning to extend the nose of the stock kit, but implementing that in production is much more complex than it sounds, and may take a while. In the meantime, it isn't too hard to extend it yourself. I'll talk you through it when you're ready.

HS-80 or equivalent servos work fine for the tail. The main concern is for durability.Talis tend to get a lot of bumps, getting snagged in doorways. etc., so you need something with gears that don't get stripped easily by such things. HS-60's would work if your linkages are perfect, but a little marginal on torque if there's any friction. The spoilers don't need much, some GWS Pico servos or equivalent are fine. The big limitation there is finding something thin enough to fit in the wing, you have a depth of about 7/16" to work in. The plans show a short pushrod to connect each servo to its spoiler (there is a short piece of stainless steel aircraft safety wire included in the kit for this), to make sure the spoiler can't suck open in flight. However, some folks use a small rare-earth magnet to hold the spoiler closed, and just let the arm on the servo push up against a small 1/64" ply plate on the underside of the spoiler to open them.

Dimeflyer

09-24-2012 01:15 AM

Good luck guy sailplanes are great to play with !!
George

pd1

09-24-2012 01:35 AM

Nice pick Steve. subscribed.

Stevephoon

09-24-2012 04:22 AM

Quote:

Originally Posted by Don Stackhouse
(Post 883178)

.... For basic sport flying, 180 watts is plenty, the plane will go nearly vertical on that. 250 watts could be good for some types of competition. ...
....
HS-80 or equivalent servos work fine for the tail. ...
...
The spoilers don't need much, some GWS Pico servos or equivalent are fine. The big limitation there is finding something thin enough to fit in the wing, you have a depth of about 7/16" to work in. ...

Thanks for this info Don. I'm basically looking for a "Sport" setup, but I'd like to be able to try some ALES type competitions if I feel I get good enough. But another look for some yet lighter motors maybe in order.

I never thought to on check the depth requirement for the spoiler servos. Thanks for the warning...

And pd1 and Dimeflyer... Welcome to the thread!

Steve

Dimeflyer

09-24-2012 07:18 PM

I am thinking about joinning you on this build but I don't yet have a camara that will
work with my cpu or the forum size pics so I can't put up pics , am trying to save up the money for a better one so I can show what I am doing !
I just recieved a plan for the Gentle Lady sail plane so I will be working with that over the winter for the spring flying weather !!
George

AEAJR

09-25-2012 10:32 AM

I won't be building with you but I will be following.

I will be posting a link to this thread for my club. We have many in the club who like to build and the DJAerotech Chrysalis has a very good reputation both as a kit and as a great flying pure glider. I am sure it will be excellent as an e-glider too.

The 260 watt motor being used seems a very good choice for sport flying. For anyone who might be thinking of this for ALES, altitude limited electric soaring contests, I would suggest 130+ watts/pound as a good minimum target in order to be able to hit your 200 meters in 30 second goal.

If the finished weight target of 37 ounces is reached that would be about a 300 watt motor. I might target 320 to be safe.

The ALES format has become very popular in our club and across the country so I think taking this into account in the build plan might be a good idea. But I realize that this may not fit into your design goals.

Stevephoon

09-25-2012 05:29 PM

Quote:

Originally Posted by Dimeflyer
(Post 883304)

I am thinking about joinning you...
forum size pics so I can't put up pics , am trying to save up the money for a better one so I can show what I am doing !
I just recieved a plan for the Gentle Lady sail plane so I will be working with that over the winter for the spring flying weather !!
George

Feel free to join along. Sizing pictures can be a pain. I have switched to just using a lower relolution on my camera so the pictures are directly uploadable.

Quote:

Originally Posted by AEAJR
(Post 883386)

...

The 260 watt motor being used seems a very good choice for sport flying. For anyone who might be thinking of this for ALES, altitude limited electric soaring contests, I would suggest 130+ watts/pound as a good minimum target in order to be able to hit your 200 meters in 30 second goal.

If the finished weight target of 37 ounces is reached that would be about a 300 watt motor. I might target 320 to be safe.

...

Hi Ed,

This is some good info on power levels. I did not realize that I would need that much power to reach 200 m in the time frame needed for ALES competitions. Did you know that I blame you for this build? It was one of your threads on how much fun you have flying sailplanes are that made me think I need one.

Also, thanks for your primer on electric flight… It has helped me greatly over the last few years.

Steve

AEAJR

09-26-2012 12:41 AM

Glad I could get you addicted and help you with your electric habit.

your local RC pusher!

Ed

Dimeflyer

09-27-2012 02:26 AM

Who needs a pusher to get hooked on building models ?
I sometimes think I was born to build things of all kind !
I used to think hunting Bambi and his Mom was fun but after Nam
I lost the need to do that !
Hope all be well and safe !!
George

vicrider

09-27-2012 11:55 PM

Subscribed, Planing on doing one of these myself.

Stevephoon

09-28-2012 02:34 AM

Welcome aboard vicrider....

Well, I'm thinking about sticking with my original thought of a 260 watt motor for now.. Most of the motors I can find in that are rated 320 watts and above also weigh more than I'd like. Since the 260 watt motor is a 35-30 size, it will be easy to swap out for a slightly more powerfull (but longer and heavier) one if I need to.

The weather is great here in Michigan for a change... So, still no building yet. Just flying! (and work and fixing things around the house and fixing my son's car and yard work..........)

Steve

AEAJR

09-28-2012 01:43 PM

Quote:

Originally Posted by Stevephoon
(Post 883719)

Welcome aboard vicrider....

Well, I'm thinking about sticking with my original thought of a 260 watt motor for now.. Most of the motors I can find in that are rated 320 watts and above also weigh more than I'd like. Since the 260 watt motor is a 35-30 size, it will be easy to swap out for a slightly more powerfull (but longer and heavier) one if I need to.

The weather is great here in Michigan for a change... So, still no building yet. Just flying! (and work and fixing things around the house and fixing my son's car and yard work..........)

Steve

This is your build buddy, and I am not really a builder so take what I say with the usual grain of salt.

The original design was based on a heavy Speed 600 motor. You are going to put in a light brushless. So that weight has to be made up somehow.

Several people in our club built Bird of Time kits and some extended the nose to reduce the amount of lead needed to balance. Worked well but that long nose was much more prone to breakage. So a little bit heavier brushless with a bit less extension of the nose might not be a bad thing.

Just food for thought.

Dimeflyer

09-28-2012 03:40 PM

You could try making that knose with a little more strength when you extend it and
could reduce the excess added weight by useing some 1/8" ply for doubleing
the sides of it ?
George

AEAJR

09-28-2012 04:02 PM

Quote:

Originally Posted by AEAJR
(Post 883766)

This is your build buddy, and I am not really a builder so take what I say with the usual grain of salt.

The original design was based on a heavy Speed 600 motor. You are going to put in a light brushless. So that weight has to be made up somehow.

Several people in our club built Bird of Time kits and some extended the nose to reduce the amount of lead needed to balance. Worked well but that long nose was much more prone to breakage. So a little bit heavier brushless with a bit less extension of the nose might not be a bad thing.

Just food for thought.

I should have added why that nose might be more prone to breakage.

Because gliders do not normally have landing gear, belly landing is the norm. As such the nose can take more of an impact than would normally be seen on a plane with landing grear. So a slightly nose low landing will be taken on that extended nose.

Again, I am no builder and don't even dream of telling you how to do your build. But if this is your first glider, these are factors that might not be apparent.

So some stronger stringers out to the nose, top and bottom, might be in order. The stress is more compressive, at the top of the fuse, than the bottom as wood tends to be strong in tension than compression.

Again this means weight in the nose which might reduce the length of the nose.

Don can probably speak to these things better than I can and he may even feel that my comments are not valid. I would accept his judgement. I only bring these up for your consideration before you apply glue to wood.

I think your greatest weight saving will be in the battery. I would expect the long nose/light motor to be a much smaller saving by comparision. So if you can find a way to move that battery forward as far as possible that would be an excellent way to make up for the light motor.

I had a Cox Dust Devil. ARF with a glass fuse. Built for a speed 600. Not easily extended so I ended up with a lot of lead in the nose, but I did reduce it some by moving that 3 cell lipo way forward. But even with all that lead I saved about 6 ounces just by changing to Lipo from NiCd.

Don Stackhouse

09-29-2012 01:23 AM

First of all, the Chrysalis series fuselages do not have stringers in the nose. From the nose to a little aft of the wing trailing edge they have 1/8" lite ply doublers in the fuselage sides. The sides have a balsa sheet outer skin outside fo the doublers. The belly is balsa sheet, but there is a birch ply skid plate under the nose and wing, which also acts as a tension member in the case of "dork" landings. It's all pretty durable.

The recommended method for xtending the nose involves a long scarf cut in the doublers, angling forward from just in front of F2 (the wing leading edge bulkhead), about 30 degrees below horizontal. After splicing in the extension, reinforce the two splices with 1" glass tape and epoxy on the inside faces of the doublers. The balsa outer skins will reinforce the outer faces of the doublers sufficiently. Running the splices in this manner minimizes the factors that would encourage buckling failures on the top edges of the sides, or tension failures on the bottom edges.

We use the same balsa pieces and ply belly plate in the electric as in the sailplane kit, so these will be long enough to cover the extended area without any additional splices. There are some splices in the balsa pieces, but those occur back under the wing in a way that is not structurally critical.

While the lighter motors in common use these days are a contributing factor, the biggest cause of C/G problems is poor workmanship in th tail section, particularly using too much glue, and not enough sanding in the corners.

Stevephoon

09-29-2012 02:36 AM

1 Attachment(s)

Don, thanks for reiterating your thoughts on how splice in the nose extension. I've seen you mention it before over on RCGroups and think it should be an easy change.

I've attached a picture of the inside ply fuselage sides. These are the pieces that need splicing. On the outside another basla doubler is added then cut and sanded to shape. There are two of these per side that when put together, run the entire length of the fuselage. So the outside front will also have a solid piece over it for strength. A little fiberglass tape and epoxy on the inside seams and it should be plenty strong. Triangle stock could be added to the bottom sides in the splice area if needed as well.

With this is mind, I did order the following parts tonight from HeadsUpRc.

I've never tried either of these servos before, so a little validation of their operation will be needed. (Not quite sure how to do this, but I'll try)

My plan is to start on the fuselage right after I get the motor and make sure it will easily attach to the firewall. Hopefully next week sometime.

Steve

Don Stackhouse

09-29-2012 03:04 AM

The only trick on the splicing is you have to angle the scarf cut just right to go above the hole for the wing hold-down dowel. Of course if you're planning to use the bolt-on option instead of rubber bands, it's not an issue.

tom1968

09-29-2012 04:01 AM

Subscribed. The Chrysalis has a great reputation.

260 watts should be just about right for ALES performance. I just upgraded my Skybench Li'l Bird 2M from about 175 watts to 220. At 175 watts it would climb to about 170m in 30 seconds. With 220 watts it hits 200 meters. The Li'l Bird weighs 32 oz so if you're at 37 with 260 watts you should get about the same result.

bluzjamer

09-29-2012 04:37 AM

Steve you could always just hang the motor out front instead of lengthening the fuse.
My glider club prez just bought one of these, I gave him the link. I'm repowering my Skimmer and Vista and Jeff reccomended the firepower 10...I think it is a little over kill but will try them. Can always throtle down...I was going to go with a slowfly 450. They are about the same type of planes as this one. I try to build as little as I can and usually go with arfs. At my age and with my space I'd rather fly than build.

offtom

09-30-2012 01:33 AM

Always enjoy your builds Steve. I'm looking forward to this one.

k8zfj

09-30-2012 03:03 PM

Started my build last Monday , by first slicing the instructions into square pages for easier reference. Next the ribs got labeled & stacked, along with organizing the similar pcs of wood parts, then off to slicing off front of fuse doublers to extend the nose.
AEAJR has rite approach re. Building, soon I need to take that route too

Don Stackhouse

09-30-2012 04:34 PM

Quote:

Originally Posted by k8zfj
(Post 884013)

Started my build last Monday , by first slicing the instructions into square pages for easier reference.

Another alternative is to just zig-zag fold them along the horizontal boundaries of the steps.

When we frst put the kit in production, we looked at the option of printing a booklet vs. putting them on another plans-sized sheet. Economically the sheet approach worked better. We were also figuring that a lot of beginners would have past experience with plastic models, and we wanted to duplicate that look, to help them feel at home with it.

Today we might choose differently. My guess is we will probably go with a booklet for the 3-meter, if I can ever find the time to finish it. We did that, including color photos, on the instructions for the Roadkill Series models.

The other thing we've talked about is a construction DVD that we would sell separately. However, that requires a huge amount of time and resources to put together, which with my "day job" (designing and developing UAV's) is tough to fit into the schedule right now.

Quote:

Next the ribs got labeled & stacked,...

Hint: If you are planning to cover the plane with transparent covering, label the ribs with a Hi-liter felt pen the same color as your intended covering color. The labels will "disappear" when you cover the plane.

k8zfj

09-30-2012 05:39 PM

When we frst put the kit in production, we looked at the option of printing a booklet vs. puttingthem on another plans-sized sheet. Economically the sheet approach worked better. We were also figuring that a lot of beginners would have past experience with plastic models, and we wanted to duplicate that look, to help them feel at home with it. .....

The way you did it economically makes good biz sense!

Stevephoon

10-01-2012 01:51 AM

1 Attachment(s)

Quote:

Originally Posted by Don Stackhouse
(Post 883841)

The only trick on the splicing is you have to angle the scarf cut just right to go above the hole for the wing hold-down dowel. Of course if you're planning to use the bolt-on option instead of rubber bands, it's not an issue.

Don, this confused me... I was not planning on the cut being this far back. I was thinking of two slightly offset cuts would be the way to go. If I'm inserting a 1.5 in section, I'd cut one side .75 in in front of the other. This wat none of the cuts would line up. So you are suggestion that the cut should be farther back so that F2 is glued over the cut? Is that correct? I've drawn a couple of lines on mine, I was originally thinking even more forward than here. Do you have a picture you can share with the suggested spot to cut indicated?

Quote:

Originally Posted by bluzjamer
(Post 883851)

Steve you could always just hang the motor out front instead of lengthening the fuse.
....

bluzjamer, welcome to the build. That was was my initial thought as well, but I'n not very good at making cowels and I'd end up covering up the cool air intakes. (Small cutouts in the balsa in the sides of the nose) I thought this way would be easier for me.

Quote:

Originally Posted by k8zfj
(Post 884013)

Started my build last Monday , by first slicing the instructions into square pages for easier reference. Next the ribs got labeled & stacked, along with organizing the similar pcs of wood parts, then off to slicing off front of fuse doublers to extend the nose.
AEAJR has rite approach re. Building, soon I need to take that route too

Hi k8zfj. I too have cut the plans apart, but that's still the extent of my progress. How/where did you cut the doublers and how long are you extending your nose?

I can get started as soon as my son returns my glue and clamps. Something he promised to do today, but nope... I also pulled out my 1/8 in ply sheet (I only have one) and it's now warped. I put it under a bunch of weights to try and flatten it out.